Position Control of a 12V DC Motor (REMOVED)

Other Hardware Robotics
1

:grin: :smiley: :smiley: :sleeping: :frowning: :smiley: :sleeping: :. :slight_smile: :0 :zipper_mouth_face:

Couldnt delete the forum so i had to do this, IMMENCE Gratitude for everyone who replied, apprently I wasnt supposed to post deatils of my project online, school rules :-\ , Sorry and Thank You again!!!

2 
motorSpeed = map(motorSpeed, -255, 255, 0, 255);
      if (motorSpeed >= 0)
      ...
      }
      else
      {

How is this supposed to evaluate false if you map all your values to be zero or greater? get rid of the map() and it should work.

3

Ok, there's some stuff I didn't catch at first glance.//the driver is weird as -255 turns the motor slowly and -1 turns it at fullspeed That's because analogWrite takes an unsigned 8 bit integer and you're shoving a negative number into it. Change the analogWrite in these parts

if(motorSpeed >= 0)
{
    ...
}
else
{
    ...
    analogWrite(pwmPin, motorSpeed);

to analogWrite(pwmPin, abs(motorSpeed)); Your main problem is likely caused by this while statement while (encoderTicks >=500 && timer > 3000) Once your motor moves 12 ticks back from desiredPosition1 (512) , this loop will exit. Try replacing that while statement with this

while (timer < 3000){}//delay 3s
		
while (encoderTicks > desiredPosition2)
{
    ...

Also, it won't hurt to constrain motorSpeed for the second movement in the same way you constrained it for the first movement. Plop it in where the old map() used to be.

4

Appreciate the feedback, but using

while (timer < 3000){}//delay 3s

Would not allow the control system to run as it would delay 3 second regrdless encoderTicks reaching desiredposition1

I too think, that section of code is the culprit. How do you think I can delay the system without affecting the PID?

5

yeah, your loop is set up strangely. Just put each movement in its own while(1) loop and break out of it whem the motor is at the right position (encoderTicks == desiredPosition). Ideally you would make some sort of moveMotor() function that takes the desired position as an argument.

6

I really dont know how to use the break fucntion, its really confusing. And I didnt get you, while(1) where?

7

If the motor only rotates 45 deg., then maybe just use a pot to determine the position as a servo does.

8

Using an encoder is a must, sadly!

9

eyasfazul:
Using an encoder is a must, sadly!

Just looking at the motor gizmo, how are you going to establish a zero start position and calibrate the encoder to the start position? Does the motor setup have a rotation hard stop?